1. Field of Art
The present invention relates to radiofrequency communication protocol and, more particularly, a flexible system comprising a network of a transceiver and several human interface devices (HIDs) using either unidirectional or bidirectional mode to communicate with the transceiver, as well as optimization of a transmission between the transceiver and the HIDs, and pairing the transceiver with the HIDs.
2. Description of the Related Art
A network of wireless devices is often configured with a host transceiver communicating with one or more devices. The devices communicate through a conventional wireless communication protocol. Among existing communication protocols, low frequency protocols have the advantage of being simple and low cost. However, although systems using such protocols are less complex, they also have significant limitations that include lower bit rates and shorter communication ranges. High frequency protocols have higher bits rates and longer ranges. However, systems using such protocols are more complex to design and implement. This results in greater development and implementation costs as well as increased use of resources such as transmission and processing power, which increases power consumption.
In the context of a conventional networks of HIDs, the HID devices are either unidirectional or bidirectional devices that communicate with a transceiver. Generally, a network with unidirectional devices allows use of a low cost and simple transceiver in particular in terms of electronics and firmware. However, unidirectional transmission requires transmitting additional, redundant information in order to compensate the lack of reliability of the link. Likewise, a network with bidirectional devices generally allows reliable data transmission. However, such configurations cost time and energy because devices must wait for acknowledgement from the receiver. In addition, such conventional networks do not offer the necessary flexibility for various kinds of applications.
In addition to the problems outlined above, other problems also exist with conventional HID configurations (or applications). For example, a conventional communication network of HIDs is generally implemented within low and middle radio frequency Industrial Scientist Medical bands (ISM bands). However, some ISM bands do not have worldwide acceptance and approval. To address this problem, many HID configurations use a high radio frequency ISM band, for example 2.4 GHz.
The use of such high frequency bands is not without costs. It increases system complexity, and in turn, costs. In addition, such systems increase power consumption. This reduces the operational time of battery powered type devices. Moreover, devices operating in this same frequency band have problems of collision with each other. For example, in the 2.4 GHz band, data transmission collisions may occur in devices of types that are communicative through a Bluetooth protocol, wireless local area network (WLAN) protocol, or as a cordless phone. This causes a reduction or overall failure of data throughput.
Also known is communication protocols that handle multiple devices on a single host, for example, Bluetooth host networks. However, Bluetooth is a very complex protocol. It requires significant hardware and software resources to be present in each node in order to work. Although Bluetooth devices in some configurations give an appearance of being unidirectional devices, the communications are in fact bidirectional, not unidirectional. Specifically, careful study of the low-level communications structure shows that the underlying radio communication is bidirectional, even though transmission in one of those directions does not transport useful user data. Thus, the extraneous data send in such devices unnecessarily occupy bandwidth and increases power consumption.
Hence, there is a need for a system and process that is configured for unidirectional or bidirectional communication between transceiver and a HID, that provides robust communication without increasing power consumption and without significantly increasing operational and manufacturing costs. In addition, there is a need for a radio frequency (RF) sub-system and associated processing configuration that remains active, without waiting in vain for RF reports, while allowing for predictability that the next report could be expected only after some passage of time.